#1 The Undertaker vs Shawn Michaels (WrestleMania XXV)

Were you expecting some other match on #1? Because if you were, you haven't seen this magical encounter from WrestleMania XXV.
By 2009, barring the two face-offs at Royal Rumble in 2007 and 2008, it had been over a decade since The Undertaker and Shawn Michaels had faced each other in a one-on-one match. However, with The Undertaker's Mania streak becoming more and more sacred with every passing year and both nearing the twilight of their careers, WWE took the decision to finally bring them together for a program at Mania XXV. And boy, did they deliver.
While the pre-match expectations from this match were not very high, considering their ages, the two shattered all the expectations and wrestled a match that would be used as a prototype for a number of future Mania matches. With more than half a dozen of false pinfalls, the excitement and craziness from the crowd for this match was at a level that was never seen before in the WWE.
For more than 30 minutes, The Phenom and Mr. WrestleMania countered each other's moves and hit each other with everything that they had before The Undertaker somehow managed to catch Michaels mid-air, hit him with a second Tombstone Piledriver and pinned him to bring an end to what still is not only the best WrestleMania match, but arguably the best match inside a WWE ring.
WWE made several mistakes with Money in the Bank?